Means for controlling air flow from a wall duct



Nov. 3, 1959 F. BARNWELI. 2,910,927

MEANS FOR CONTROLLING AIR FLOW FROM A WALL DUCT Filed Jan. 21, 1959 2 Sheets-Sheet l mi, S /5 E ff i I wie M (za fg M /7 1.' I 7 X/ /71/ Q o 5% 47 -A V A/1/\ /Jf l Vf/ y L .W ff f; l l 4/ fj`\ i X7 O d f .iii if /y "H2452 HI INVENTOR. :f 34 i f2 /ea/M/ 54E/wwf@ i7 BY 73/ Nov. 3, 1959 l. F. BARNWELL. 2,910,927

MEANS FOR CONTROLLING AIR FLOW FROM A WALL DUCT Filed Jan. 21. 1959 2 Sheets-Sheet 2 INVENTOR. 7/ /l//A/ 54E/vivan BYM United States Patent O MEANS FOR CONTROLLING AIR FLOW FROM A WALL DUCT Irving Frederick Barnwell, Baisley Park, N.Y.

Application January 21, 1959, Serial No. 788,112

7 Claims. (Cl. 98-118) This invention relates to means for controlling the flow of air or a gas from a duct or conduit, and the main object of the invention is the provision of a novel manually operated door, damper or the like by means of which the flow of air from an elevated duct in a wall may be readily shut olf `or varied in degree from a position below the duct.

A specific application of the invention relates to the control of the flow of air from a conduit or duct through which cooled air is adapted to ilow in an air-cooled or refrigerated room, such ducts being generally located in a wall near the ceiling of the room. It is well known that in many such installations the cooled air blowing into the room causes a draft which is not only discomforting to persons near Vby but which also frequently is the cause of catching cold. The present invention enables a person to shut off the inow of cooled air into the room, or to diminish its ow or volume, from a position well below the duct as, for example, even while sitting in a chair at a desk. Further, the present invention dellects the incoming cool air to prevent it from sweeping across the room.

, The above broad as well as additional and more specific objects will be clarified in the following description wherein reference numerals refer to like-numbered parts in the accompanying drawing. lt is to be noted that the drawing is intended primarily for the purpose of illustration and that it is therefore neither desired nor intended to limit the invention necessarily to any or all of the exact details of construction except insofar as they may be deemed essential to the invention.

Referring briefly to the drawing, Fig. 1 is a front elevational view of the air control means applied to a wall outlet or duct of an air refrigeration system.

Fig. 2 is a sectional View taken on the line 2-2 of Fig. l.

Fig. 3 is a view similar to Fig. 2 but showing the door in fully opened position.

Fig. 4 is a sectional view taken on the line 4-4 of Fig. 2.

Fig. 5 is a sectional view taken on the line 5--5 of Fig. 2.

Fig. 6 is a perspective view ofthe device with the door in fully closed position, with parts broken away and partly in section.

Referring in detail to the drawing, the numeral 10 indicates the wall of a room having an opening 11 therethrough in which a louvre 12 is mounted at the outlet of a cooled air duct or conduit, not shown.

A rectangular frame 13 is secured, as by screws 14, against the wall around the opening 11. A door 15 is suspended on horizontally aligned hinges 16 from the upper panel 17 of the frame 13 so that it normally hangs in vertical position to close the opening 11. Strips 18 on the outer surface of the door extending beyond its length serve both to seal the space between the door ends and the frame and to provide limit stops to inward movement of the door.

2,910,927 Patented Nov. 3, 1959 A horizontal support 19 is secured to and extends forward from the lower frame panel 20, and a vertical wheel 21 is rotatably mounted thereon on a pin 22. The rim of the wheel is provided with at least two, and preferably three, spaced radial notches; three such notches are shown at 23, 24 and 25. An arm 26 having a wide end 27 and a reduced end 28 has the latter joined by a short chain 29 to an eyelet 3l)V on the lower edge of the door. By means of two pins or the like 31 and 31a, the wide end of the arm is secured to the wheel at the rim of the latter in approximately tangential position. The pin 31a is elongated and has a chain 32, which is also long, suspended therefrom.

A pawl 34 is pivoted substantially intermediate its length on a pin 35 extending through the support 19. Actually the pawl is composed of two parallel pawl arms 34a and 34h having the pivot pin 35 extending between them and integral therewith. A pin 36 ioins the lower ends of both pawl arms, and a connector 37 is positioned between these arms and suspended pivo'tally from the pin 36. At their upper orouter ends the two pawl arms are joined by a pin or roller 39. Two coiled springs 40 are provided, each secured at one end to the lower end of a pawl arm and at the other end to a fixed anchorage such as a screw secured to the frame panel 13. A long chain 3S hangs from the connector 37.

Fig. 2 shows the door in fully closed position. In this position of the door, the pawl pin 39 registers in the notch 25 of the wheel 21 and is maintained there by the springs 4t). Also, the chain 29 between the door and the arm 26 is slack. To open the door to an intermediate position, not shown, the chain 32 is pulled downward, thus rotating the wheel 21 clockwise, Figs. 2 and 3. Owing to the rounded walls and particularly the open ends of the notches 23, 24, and 25, upon pulling the chain 32 downward and thus swinging the wheel 21 and the arm 26 clockwise, the pawl pin 39 will be ejected from its notch 25 against the force of the springs 40, and as soon as the wheel has been turned sufficiently the pawl pin will be forced by the springs to register in the notch 24. To open the door to its extreme position, the operation of pulling the chain 32 is repeated, whence the pawl pin will first ride out of the notch 24 and enter the notch 23. If only two notches are provided, such as, for example, 23 and 25, the door will be fully opened upon pulling on the chain 32.

To restore the door to either the intermediate position or the fully closed position, it is only necessary to pull down on the chain 38, thus extracting the pawl pin 39 from the notch in which it registers to enable the door to move toward the wall, i.e., clockwise, by gravity. It is to be noted that in each position in which it is releasably held, the door is stable; and no matter which notch the pawl pin registers in, rather than registering in the base of the notch the pin 39 rests against the two legs of the forked extremity 33 of the support 19. It is also to be noted that although the notches 23, 24 and 25 have been defined above as radial slots they need not actually be radial but may be aligned with a chord extending to the left of the center of the wheel 21, Figs. 2 and 3.

In order that the door 15 may be locked in any of the three possible positions described above, an arm 41 having a longitudinal slot 43 may be hinged or pivoted at 42 to the frame panel 17, with a pedestal 44 secured to the door and provided with a wing nut and bolt unit 45 rotatable in the pedestal and registering in the slot 43. Under normal working conditions, the unit 45 is loose so that during operation of the door the stem of the unit 45 slides in the slot 43.

The material of which the entire device is made, eX- cept for the hardware, is preferably a plastic material such as, for example, one available on the. market under the trademark Flexiglass, andthe material may be provided in any desired color or color combinations.

The invention having thus been described, what is claimed and desired to be secured by Letters Patent, is as follows;

1. A device for the control of the flow of air into a room from a duct in a wall comprising a rectangular frame secured to the wall around the duct having a door hinged on a horizontal axis to the upper horizontal panel of the frame, a horizontal support having its outer end forked extending into the room frompand at right angles to the lower panel of the frame, a Wheel rotatably mounted in vertical position in said forked end of the support, an arm xed to the wheel extending substantially tangentially from the wheel in the general direction of the wall, an articulated member having one end thereof securedto the end of said arm remote from the wheel and the other end thereof secured to the door below said axis, said arm when the door is closed against the duct being positioned substantially horizontally and having said end thereof proximate to the door, means for rotating said wheel through an arc greater than the length of said member in a direction to swing said end of the arm outward from the door and hence through the medium of said member swinging the door to a given open position, releasable means partly on said wheel and partly on said lower panel of the frame for automatically releasably locking the wheel in a position wherein said door is in said open position, and means for releasing said releasable means, said door upon release of said releasable means swinging by gravity to closed position.

2. A device according to claim l, said releasable means comprising a pawl composed of two parallel arms positioned vertically on the sides of said support, said pawl arms having a pin rigid therewith positioned approximately intermediate their length and passing rotatably through said support at a position between the forked end of the support and said frame, said pawl arms having a second pin rigid therewith on one end thereof, said wheel having at least two relatively deep circumferentially spaced approximately radial notches, resilient means normally urging the pawl to swing in a direction to urge said e 4 second pin against the rim of the wheel and into one of said notches when the pin is aligned with a notch, said Asecond pin being aligned with one of said notches when the door is in said open position and being aligned with the other of said notches when the door is in said closed position.

3. A device according to claim 2, said means for releasing said releasable means comprising a connector pivotally mounted between the other ends of said pawl arms having a pull chain suspended therefrom.

4. A device according to claim 2, said notches having a depth such that when a notch is in position to be enl tcred by said second pin of the pawl the base of the notch is positioned below the top surface of said support whence said second pin rests upon said top surface of the support.

5. A device according to claim 2, said means for rotating said wheel in said lust-named direction comprising a pull chain suspended from said wheel at a point spaced outward with respect to said frame a distance beyond the axis of the wheel.

6. A device according to claim 2, said resilient means comprising two coiled springs each having one end thereof secured to said lower portion of the frame and the other end thereof secured to said other ends of the pawl arms.

7. A device according to claim 3, said means for rotating said wheel in said first-named direction comprising a pull chain suspended from said wheel from a point spaced outward with respect to said frame a distance beyoud the axis of said wheel.

References Cited in the le of this patent UNITED STATES PATENTS Norway Sept. 28, 1953 

